Two SRY-negative XX male brothers without genital ambiguity

Hum Genet. 1997 Oct;100(5-6):606-10. doi: 10.1007/s004390050561.


We report a Mexican family in which two sibs were identified as "classic" XX males without genital ambiguities. Molecular studies revealed that both patients were negative for several Y sequences, including SRY. A review of familial cases disclosed that this is the first family where a complete male phenotype was observed in Y-negative XX male non-twin brothers. These data suggest that an inherited loss-of-function mutation, in a gene participating in the sex-determining cascade, can induce normal male sexual differentiation in the absence of SRY.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Centromere / genetics
  • DNA-Binding Proteins / genetics*
  • Female
  • Humans
  • Hypogonadism / genetics*
  • Karyotyping
  • Kruppel-Like Transcription Factors
  • Male
  • Mexico
  • Models, Genetic
  • Nuclear Family
  • Nuclear Proteins*
  • Pedigree
  • Sex Chromosome Aberrations / genetics*
  • Sex-Determining Region Y Protein
  • Transcription Factors*
  • X Chromosome / genetics*
  • Y Chromosome / genetics


  • DNA-Binding Proteins
  • Kruppel-Like Transcription Factors
  • Nuclear Proteins
  • SRY protein, human
  • Sex-Determining Region Y Protein
  • Transcription Factors
  • ZFY protein, human